Partial least squares method in the analysis of resting-state functional magnetic resonance: study of the aging brain and autobiographical memory

• Grant number: 12/11898-5
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: January 02, 2013
• End date: January 01, 2014
• Field of knowledge: Health Sciences - Medicine - Psychiatry
• Principal Investigator: Geraldo Busatto Filho
• Grantee: Luiz Roberto Kobuti Ferreira
• Supervisor: Anthony Randal Mcintosh
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Toronto (U of T), Canada
• Associated to the scholarship: 10/17083-8 - Brain function during autobiographical memory recovery in elderly subjects: a functional magnetic resonance imaging study, BP.DD

Abstract

Population aging is an enduring demographic change. It represents a challenge because it is related to higher prevalence of neurodegenerative diseases; moreover, normal aging is associated with cognitive decline. Functional magnetic resonance imaging (fMRI) provides the opportunity to study the brain and the resting-state fMRI has been studied intensively due to its feasibility and potential for future use in clinical practice. Brain connectivity changes occur during aging, are related to cognitive performance and can be studied using resting-state fMRI. The posterior cingulate cortex (PCC) has been the focus of neuroimaging studies of aging and has an important role in memory and self-referential processing. These domains are essential for autobiographical memory performance, which is worse in the elderly. A current challenge in the field of neuroimaging and brain connectivity regards the analysis of fMRI data. One method, Partial Least Squares (PLS) is a versatile multivariate technique that has been validated for fMRI data analysis by Prof. A. R. McIntosh from the University of Toronto.Objectives: to identify differences in resting-state functional connectivity between young and older adults applying the PLS method (using the PCC as a seed region). In addition we will verify if there are correlations between autobiographical memory performance and functional connectivity.Methods: resting-state fMRI will be acquired from healthy subjects divided in two groups: 20 young adults and 20 elderly subjects. Then we will record twelve autobiographical events from each participant and these will be scored in accordance to standardized methods. fMRI data will be preprocessed using SPM8. The cardiorespiratory noise will be suppressed using Aztec software. Data will be processed using the PLS method: the data from the PCC and the remaining brain regions will be computed in two matrices; information from these will be combined, resulting in a correlation matrix; this will be decomposed, generating latent variables that express the relationships between the seed region and the rest of the brain. A permutation test will be performed to verify statistical significance (p<0.05). The correlation map of the young adults group will be compared to the map of the elderly. We will also test for correlations between autobiographical memory performance and resting-state functional connectivity. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FERREIRA, LUIZ KOBUTI; BROCANELLO REGINA, ANA CAROLINA; KOVACEVIC, NATASA; MORAIS MARTIN, MARIA DA GRACA; SANTOS, PEDRO PAIM; CARNEIRO, CAMILA DE GODOI; KERR, DANIEL SHIKANAI; AMARO, JR., EDSON; MCINTOSH, ANTHONY RANDAL; BUSATTO, GERALDO F.. Aging Effects on Whole-Brain Functional Connectivity in Adults Free of Cognitive and Psychiatric Disorders. CEREBRAL CORTEX, v. 26, n. 9, p. 3851-3865, SEP 2016. (10/17083-8, 12/50329-6, 11/00475-3, 12/11898-5)

FERREIRA, LUIZ K.; TAMASHIRO-DURAN, JAQUELINE H.; SQUARZONI, PAULA; DURAN, FABIO L.; ALVES, TANIA C.; BUCHPIGUEL, CARLOS A.; BUSATTO, GERALDO F.. The link between cardiovascular risk, Alzheimer's disease, and mild cognitive impairment: support from recent functional neuroimaging studies. Revista Brasileira de Psiquiatria, v. 36, n. 4, p. 344-357, OCT-DEC 2014. (12/50329-6, 12/11898-5)